Airlines around the world are monitoring a pair of volcanic eruptions in two different sites. This volcano is spewing ash into the air. Meantime, scientists are keeping a close eye on another volcano in Iceland. Bob woodruff has the story. Reporter: Today, plumes of white steam rising thousands of feet in the air from a half-mile crack in the Earth, the long awaited eruption of Iceland's massive bardarbunga volcano. Their fear, a huge eruption could send a plume of ash across Europe. We traveled to Iceland this week, a country of more than 30 active volcanos. Volcano activity certainly isn't new to Iceland. The volcanos have been blasting for millions of years. As you head east you see everything is black, filled with lava, the rocks and the ash. But an eruption's effects can be felt thousands of miles away. In 2010, another Icelandic volcano sent ash drifting across Europe, cancelling more than 100,000 flights. Passengers stranded for days. Today's explosion began under Europe's largest glacier. Scientists feared an explosion of ash created when hot magma hits ice. The power of a decent explosion in a glacier is many Hiroshima bombs. Reporter: That didn't happen today. So far, scientists have not detected any ash. Encouraging news. People who live in this remote part of the world telling me they're prepared for whatever comes. Do you have any fear at all? No. Reporter: You've seen this before? Yes, whatever comes, it comes. Reporter: Scientists breathing easier tonight too, but still keeping watch on that steaming behemoth.

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